Syringe



A. E. SMITH SYRINGE June 21, 1949.

Filled May 51, 1947 INVENTOR.; Apr/MPE'. S/wr/f Patented June 21, 1949 UNITED STATES EBTENT OFFICE 6 Claims.

This invention relates to improvements in disposable hypodermic syringes.

The general object of the invention is to provide an improved single-use hypodermic syringe whereby medicinal compounds such as penicillinoil-wax may be administered in an eicient manner.

A more specific. object of .the invention is to provide a novel plunger .for ampule type syringes.

Another object of the invention is to provide anovel closure for the ampule of a disposable syringe.

Other objects and advantages of the invention will be apparent from the following description taken in -connection with the accompanying drawings, wherein Fig. 1 is a central sectional View of a disposable syringe showing my invention;

Fig. 2 is a view similar to Fig. 1 showing the syringe prepared for use,

Fig. 3 is a View similar to Fig. 1, sho-wing the syringe after the contents have ben discharged;

Fig. A4 is an enlarged fragmentary sectional view, and

Fig. 5 is a central sectional View, showing a modification.

Referring vto the drawing by reference character, `I show my invention as embodied in a disposablesyringe which is indicated generally at IU. As shown, the syringe includes an ampule I I, a plunger I2, a iront member I3 and a stopper I4. The ampule and plunger may bemade of plastic material while the front member I3, the stopper I4 and the piston I5 on the plunger I2 may be made of natural or articial rubber.

The ampule II is in the form of a cylinder and the punger I2 is also cylindrical and includes a reduced portion or stem I6. The stem I6 isthreaded as at II and the threads are arranged so that the forward face I8 thereof is inclined relative to the axis of the threaded portion while the portion I9 of the threads is substantially perpendicular to the axis of the threaded portion.

The piston I5 includes a threaded recess 2li, the threads of which correspond to the threads I1.. The forward end of the piston includes a recess 2I which receives the tip of a hypodermic nedle (to be later described) when the plunger is" at the limitof its forward movement. The front and rear peripheries 23 and 24 of the piston are Vrounded so that dragging and binding are reduced to a minimum when the piston moves forward or backward, as will be later described. The piston also includes peripheral grooves 25 which prevent dragging and binding.

" beyond theprotuberance.

The stopper I4 includes 4a peripheral ilange 30 which engages the end of the ampule II. The outside diameter of the flange is substantially the same as the outside diameter of the ampule. The forward end of the stopper includes a recess 3| which is closed at the inner end by a diaphragm 32. -An auxiliary stopper is arranged in the ampule and abuts the stopper I4. The auxiliary stopper has a, forwardly opening recess:I 34 and a rearwardly opening recess 35, the recesses being connected by a diaphragm 35. The recesses 34 and 35 are coaxial with the recess 3| andthe recess 34 is preferably smaller than the recess 35.

The front member I3 is in the natureV of a resilient cap and includes a peripheral shoulder or flange 4I] which is adapted to be engaged between the index and second nger of the operator while the injection is being made. The front member includes aiforwardly projecting tip 4I which has a planar forward face 4I. The front member includes a bore 42 which is coaxial with the front member and ampule and in this bore I seat one end of a hypodermic needle 43 which extends through the bore and through the diaphragm 44 at the inner end of the bore and enters the recess 34 in the auxiliary stopper but normally does not pierce the diaphragm 35.- The needle has a protuberance 45 thereon which has a hemispherical front end 45 and aplanar rear end 45'?. The needle projects forwardly at 46 The outer end 41 of the needle and the inner end 48 thereof are both sharpened as shown. A iiexible cap member 4 9, which may be made of plastic material, surrounds the needle and engages the tip 4I tightly in the position shown in Fig. 1. The tip 4I preferably tapers so that a tight lit may be had by the ca 49. In use, with the parts in the position shown in Fig. .1, the operator slightly removes the cap 49 and then by squeezing the cap and pushing it against the protuberance the point 48 of the needle is pushed through the diaphragm `36 so that the parts assume the position shown in Fig. 2, in which condition the needle communicates with the interior of the ampule. Pressure on the outer end oi the plunger I2 then causes the contents of the ampula such as penicillin-oil-wax to be injected through the needle. 'i

In using many drugs it fis essential that injection be not made lin a vein or artery and 'to determine whether the needle has been insertedr in a vein or artery, after insertion is made, the plunger is pushed slightly inwardly and then withdrawn and if the point of the needle has puncturedI a blood vessel a partial vacuum willr cause blood to be aspirated into the ampule. Thus a check is provided against improper injection.

In Fig. I show a modication of my invention. In the modification the ampule Il is similar to the ampule Il previously described. The front member 50 includes an integral stopper portion 5|. The front member has a skirt 52 which engages the exterior of the ampule Il'. The front member also includes a, shoulder 53 which, like the flange 4U, may be engaged by the ngers of the operator While the injection is being made. A projecting tip 54 on the frontmember is tapered and is provided with a cylin drical bore 55 which extends therethrough and extends part way through the corlrl portionrl and terminates short of a diaphragm 5B. A flexible cap 49 surrounds the needle 43';

The plunger I2 includes a threaded reduced portion I6 and has a recess 6D on the inner end thereof which receives the end of a needle 4.3' when the. plunger is. atitsextreme inner position. The` plunger has a pis ton l5' which has threads similar to,` the, threads I1. In the modi- Iiation the pistonis acylinder with the ends open asshQWn.

An auxiliary stopper 3 3 shown as like the stopper 3 3'previously described isarranged in the ampule Il.

Inrusethe cap 4,9n is removed and squeezedto the position shown inFig.` 5 solthat it engages the shoulder portion 115a on the needle so that the needle .maybe pushed.v inwardly through the diaphragm 56 from the position shown in Fig.5.to placethe needle incommunication with the interiorzoi theampule. The plunger I2' and asso,- ciatedparts in the modification function the same as heretofore described.

In vboth types of Vmysyringe the bores `3l and 554 areolargefenoughto receive the needle without friction l but, `on the.- other` handy ere. sufciently small. tosupnort the .needlewhile the, injection is belngmade.

The shapeof the threads ofthe stopper permits thestopper. to be moved rearwardly by the engagementuoithe teeth thereon whicharepernendicular. to theexisof the enaes. and thus strippingfofthepiston fromthe plunger is prevented.

The. uscof the auxiliary, stopper. permits the ampulet. befllledwhen certaintypesof drugs are rto lbeused prior. to lthe `time the outer stopper and capmare securedV in place.

In themodineaton itI will. be noted that. e. shoulder. 6l is provided4 on the reduced portion L6? ofthe plunger andthe piston engages this Shoulder which takes a. portion of the thrust when the piston is moved forwardly.

Frointheioreeone description .it will be. apparentthat Ihnveinvented a novelA disprnabley hypodermic syringe whichis highly enicient in` use, which isextrernely safe and which canbe economically manufactured,

Having-.thus described my invention, I claim:

1. A. disposable syringe including, an ampule` having@ aplungerslidable i therein, said plunger comprising anelongated-body having. a forwardlyk'extendingf-reduced portion, a pistony having-.arecess receiving saidnreducedportion, a stopper inrscid empirica. seidastonperrhev-ing: ana-XM1. bore, an., auxiliaryvstopperaadjacent-to said rst-.g stopper.;` Sinldf` auxiliary-1 stopper Ahaving aligned inner and outerrecessesgwith adiaphragm therebe-Y tween, and aqfrontgmemberin;advance of -saidstoppen sa idfiirst-front\member having afingerl having a bore with a diaphragm closing the inner end of said bore, and a needle in said bore and having its inner end disposed in the outer recess of the auxiliary stopper and spaced from the auxiliary stopper diaphragm.

2. A disposable syringe including an ampule having a plunger slidable therein, said plunger comprising an elongated body having a forwardly extending reducedgportion, a piston having a recess' receiving said-reduced portion, a stopper in said ampule remote from said piston, said stopper having an axial recess and having a diaphragm closing said recess, an auxiliary stopper adjacent to said first mentioned stopper, said auxiliary stopper having aligned inner and outer reoessewth adiaphragm therebetween, a front member on said ampule, said front member havingafiinger engaging shoulder thereon, said front member having a bore and a needle in said bore and having itsinner, end disposed in theouter, recess of the auxiliary stopper and spaced fromtthe auxiliary stopperdiaphragrn.

3. A1 disposable syringe including an ampule having'a plunger slidable therein, a piston onsaid. plunger, a stopper in said ampule remote, froml said piston, said stopper having an axial recess. and having a. diaphragm closing-said recess, an auxiliary stopper adjacent to said first mentioned stopper, said auxiliary stopper having aligned inner. and outer recesses with adiaphragm there. between, and a front member integral with said stopper, said front` member havinga ngerengaging shoulder thereon, said front memberhavingA a borevtherethrough .and a needle in said bore and spaced from the auxiliary stopper` dia-, phreem.

4. A disposable syringe. includingl an4 ampule having aplunger slidable therein, saidplunger comprising a cylindrical body` having aforwardly extending reduced portion, a pistonhaving arecess receiving said, reduced portion, astopperinj said ampule remote from said piston, said stopper having an axial recess and a diaphragmclosing said recess,A azfront member on said ampule, said Yfront member having a nger engaging.,shoulderl thereon, said frontmember having a bore, an auxiliary stopper adjacent to said i-lrstvxnentionedV stopper, said auxiliary` stopper having a recess and having aY diaphragm closing the last men,- (.ioned4 recess, and aneedle slidable in saidnbore,V and having its inner end in said auxiliary stopper recess;- and,` free from the auxiliary stopper dia-A Dhl'dgm.

5. A. disposable syringe including an ampule having a plunger slidable therein, said plunger comprflsinga` lcylindrical ,body having a. forwardlyv extending; reduced lportion, a ,piston .having airecess receiving-,said l reduced portion, a stopper in said ampule remote fromfsaid piston, saidstopper having an axial. recessy and having a diaphragrn closingsaid recess, alfront member on said ampule, saidfront member having alnger engaging shoulder thereon, saidfront member; having,-a forwardly projecting-rtipthereon, said frontmemberl-having a bore, an-auxilar-y stopper adjacent to saidvfirst; mentioned` stopper, saldi auxiliary-,stopperhaving a recess and having adiaphraem closinggthe` lest mentioned recess a; needle slidablein said-bore and=having itsinnen endinsaid auxiliarystopperrecess-andvffreedrerng theauxiliary stoppergdd'phragm, anda flexible; capabout theouter end Kof said needle and seatedl on thel forwardlyY projecting-L tipl on; said; front member,

6. A disposable Syringe.; i.nc1.udineY en ampule having a plunger slidable therein, said plunger having a cylindrical body and having a forwardly extending reduced threaded stem, a piston having a threaded recess receiving said stern, the rear end of said piston being spaced from the end of the body of the plunger, said piston having a rounded periphery at its front and rear ends, a stopper in said ampule remote from said piston, said stopper having an outwardly opening recess thereon and having a diaphragm closing said recess, said stopper having a peripheral flange thereon engaging the end of said ampule, an; auxiliary stopper abutting said iirst stopper, said auxiliary stopper having coaxial front and rear recesses with a diaphragm therebetween, a front member on said ampule, said front member having an outwardly extending peripheral finger engaging bead thereon, said front member engaging said rst mentioned stopper, said front member having a tapering forwardly projecting tip thereon, said front member tip having a planar front end and said front member having a bore, a needle slidable in said bore and having its inner end sharpened and normally spaced from said diaphragm, said needle having a bulbous portion spaced from said tip, said bulbous portion having a planar rear face adapted to engage the planar end of said tip, and a fiexible cap about the outer end of said needle and engaging said forwardly projecting tip on said front member.

ARTHUR E. SMITH.

REFERENCES CITED The following references are of record in the of this patent:

UNITED STATES PATENTS 

